[KPM] :kotlin-gradle-plugin-idea Make entities data classes

This is done to benefit from .equals and hashcode functions.
The goal is to keep .copy methods stable whereas using any
.component* function shall be avoided

^KT-51262

libraries/tools/kotlin-gradle-plugin-idea/ReadMe.md

@@ -1,13 +1,24 @@
 # Kotlin Gradle Plugin Models shared between IDEA import and KGP
-The classes defined in this module will be available inside the Kotlin Gradle Plugin (KGP) 
+
+The classes defined in this module will be available inside the Kotlin Gradle Plugin (KGP)
 as well as in the IDE import (GradleProject).
 
-## Binary Compatibility: 
+## Binary Compatibility:
+
 Binary compatibility can be tested by
 `./gradlew :tools:binary-compatibility-validator:clean :tools:binary-compatibility-validator:test`
 
 Binary incompatible changes have to go through a proper deprecation cycle after releases
 
 ### Unstable APIs / KotlinGradlePluginApi
-Some APIs are marked with 'KotlinGradlePluginApi' which means, that those are not kept binary compatible and are considered 'unstable'
-from the IDEA perspective. Typically constructors for models are marked like this
+
+Some APIs are marked with 'KotlinGradlePluginApi' which means, that those are not kept binary compatible and are considered 'unstable' from
+the IDEA perspective. Typically constructors for models are marked like this
+
+Non Stable by default:
+
+- data class componentX methods
+
+Kept Stable
+
+- data class .copy methods